Skylane81E
Final Approach
I hope by stall it right before impact you mean flare. Do not stall it in, shortly before his death Sparky Imerson broke his back when a student stalled it in rather than crashing ahead.
Diamond DA40 Questions
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I hope by stall it right before impact you mean flare. Do not stall it in, shortly before his death Sparky Imerson broke his back when a student stalled it in rather than crashing ahead.
Thanks for the correction. Now I understand the constant nose up attitude.
MachFly
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Try it out on your next flight, it's fun.
Wingsofglass
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+1! Also you you can try different trim settings. T/O trim and very limited stick inputs with the throttle back gets you to best glide. Trim up gets you to falling leaf.
flyingcheesehead
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You'll probably never see that data, since there's not a company with a profit motive to fund the research.
I wouldn't say that it's the be-all end-all save - It's just another tool in the box of a Diamond pilot. I'll do whatever I need to do to deal with the emergency. In a dark night engine failure scenario over unknown terrain, though, it may be the safest technique. (Not saying it is, but there's an argument to be made for it.)
I wish people would consider the BRS as just one tool in the box rather than the all-encompassing backup some people go for - The BRS is designed for otherwise unrecoverable situations - midairs (that was the original motivation), pilot incapacitation, etc. Engine failure in day VMC? I'd still find a field.
flyingcheesehead
Touchdown! Greaser!
That's *because* they're designed for 26G's, same as the Cirrus - They'll take quite a beating.
I'd sill be looking for the red handle if I tried to crash it like a Cirrus.
MachFly
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The Cirrus seat has honeycombed aluminum underneath which crushes on impact to absorb energy and protect the spine. That is different form being a 26G seat which both Cirrus and Diamond are.
I wish more companies would adopt the BRS system instead of putting it down. This has happened in the ultralight world.
As for VFR engine failure, there was (note past tense) a Cirrus pilot who felt like you. He had an engine failure at altitude and had plenty of time to choose his landing spot. On landing the nose wheel hit a small mound and flipped the plane killing him and his wife. I seem to remember that his daughter in the back seat survived. With a Diamond you have a better chance due to much less kinetic energy. An SR22 is carrying close to 2X the kinetic energy of a DA40 when landing.
From an article on AVweb, DA40 phugoid descent (not falling leaf) is 600-1200 fpm. A Cirrus under canopy is 900-1680. DA40 forward speed 48 knots. Cirrus zero. Taking the average for each the descent rates are 8.89 knots for the DA40 and 12.74 for the Cirrus. Total velocity is 48.8 DA40 and 12.74 Cirrus. Ok, I'm being sloppy with significant digits but you get the idea.The DA40 comes down under this scenario with about 10.8 times the kinetic energy of the SR22. This is before taking into account that the landing gear on the Cirrus is designed to absorb energy and the crumple zone built into the seats in the Cirrus.
The DA40 is a more benign handling plane than a Cirrus, I love the fuel tank design, it lands significantly slower than a Cirrus and carries much less kinetic energy on landing which is a safety feature. On top of all of that the structure is very strong. I just hate the "Stall it and let it fall and it will be better than coming down under the chute in a Cirrus" stuff that gets implied.
You'll probably never see that data, since there's not a company with a profit motive to fund the research.
I wasn't talking about test data. I have met people who pulled the red handle and walked away. I'll wait till I start meeting people who do a falling leaf and walk away before I think it is as safe.
flyingcheesehead
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I'm not putting down the system at all. Should I ever be in a mid-air, I hope it's in a Cirrus!
If there's anything to put down, it's the poor decisions that pilots of Cirri make over and over again to go when they shouldn't because they consider the chute an "out".
The only other thing there is to put down is Cirrus' poor fuel tank design that leads to a lot of post-crash fires.
Do you have a link to the accident report? Seems he must have been coming in really fast for a flip to kill them IMO.
Also, BTW, the number I've heard for Cirrus under chute is 1800 fpm. I think even the Skycatcher comes down at >>900fpm under the BRS chute...
flyingcheesehead
Touchdown! Greaser!
You're unlikely to meet anyone who's taken a falling leaf to the ground in a DA40 simply because the fleet is smaller AND the accident rate is much lower. In addition, like I said, the falling leaf is only one tool in a big box. Multiply all those together and the chance of it even happening is pretty small, the chance of you meeting the person is orders of magnitude smaller. But just because you haven't personally met someone who's done it doesn't mean it's a bad idea.
MachFly
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That's not the only difference. Based on how Diamond's seats are attached, the materials that they are made out of, and the angle at which they are attached Diamond's seats are much more crash worthy. Yes, they are both rated for 26Gs but not all 26G seats are the same.
MachFly
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Logically I completely agree with you. But the interesting thing is that in the past 10 years (or so) there have been 2 Cirrus mid-airs and 2 DA40 mid-airs. Both time the DA40 landed successfully and both times the Cirrus was destroyed. So I'm not sure what's better.
MachFly
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You have to admit though, you can see the advantage of having a wet wing over fuel cells. DA40 carries 40gal of fuel (50gal with aux tanks), SR22 carries 81gal of fuel....
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I've looked at a lot of Cirrus accidents including some pretty stupid ones. What strikes me is not some unique pattern but rather how similar they are to stupid things done in other planes. Now if you compare to a different mission plane then there are differences. But, why not give me examples of dumb Cirrus things caused by having a chute that aren't done in a Bonanza.
Oh data can be a harsh mistress but I'll forgive all Diamond owners on this one. The Cirrus is in the pack with other planes in this area. Diamond owners get a buy since their plane is not in the pack but better than almost all others.
You may be right. I took the numbers from the same AVweb article on the DA40 that gave the Diamond numbers.
My main point is that the BRS system works and works well. It isn't just for mid-airs. Look at the recent pull in MN when the flap broke. I posted the NTSB prelim in another thread. What frustrates me is not some guy pulling when other pilots think he should have been more macho but people dying because the pilot didn't pull. There are way too many examples of that.
Look for ERA11FA414 in the NTSB database.
Most off airport landings are successful but not all. If people survive in 85% of them then that is still much poorer than a chute pull within parameters.
You also mentioned liking the chute for a mid-air scenario. I actually think this is a minor deal. There are about 8 fatal mid-air collisions a year. Of those half involve formation flying which I don't do. Next you would need to subtract ones in the pattern at low altitude.
More likely to happen are engine out at night, engine out while over low clouds, icing due to poor decision making, and the old VFR into IMC. There have been at least three pulls due to what I believe to be maintenance issues with two involving failure to properly attach and safety wire control surfaces.
flyingcheesehead
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SR22 burns 18gph, DA40 burns 9gph (or about 7.5 gph if you run it lean of peak). I don't think the wet wing is really that much of an advantage...
flyingcheesehead
Touchdown! Greaser!
Taking your plane into the avionics shop for work on its glass panel due to unreliable instrument indications, and then taking off into a low overcast on the very first flight out of the shop, for one.
The icing one out of CO where the chute departed the aircraft is another, but I suppose anyone could be susceptible to invincibility, it's just that having the chute seems to encourage it.
BTW, again, I am not saying the chute is a bad idea.
Y'know what's odd, I've heard of that sort of thing happening on Cirri a few times (in fact, the first successful CAPS pull was due to an aileron departing the aircraft), but I don't recall hearing about other planes having so many control surface problems. Is there something about the design of the control surfaces on the Cirrus that tends to make it easier to have such problems, or do we just hear about the Cirrus ones more often because of the chute?
MachFly
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It can burn about 12gps LOP at DA40 speeds.
Obviously I prefer fuel cells, but I don't want to say that a wet wing is that bad. Notice that quite a lot of GA aircraft have wet wings, there is got to be a reason why.
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MachFly
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Y'know what's odd, I've heard of that sort of thing happening on Cirri a few times (in fact, the first successful CAPS pull was due to an aileron departing the aircraft), but I don't recall hearing about other planes having so many control surface problems. Is there something about the design of the control surfaces on the Cirrus that tends to make it easier to have such problems, or do we just hear about the Cirrus ones more often because of the chute?
I'm not 100% sure about this but I think that this flap failure is only the second time there was a control failure in a Cirrus (first being the aileron that you mentioned). Although I do admit twice in 14 years (since 1999?) is a lot.
flyingcheesehead
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Nothing wrong with wet wings... On a metal airplane. (I am, after all, flying a Mooney right now and I believe all Mooney models came from the factory with wet wings.)
The problem is that wet wings on a composite airplane lead to the fires we've been talking about.
MachFly
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That's actually what I thought for while. A few weeks ago I started researching the Cessna Corvalis and I was unable to find a single crash where it cough fire (and it also has a wet wing). So maybe it's just something specific that Cirrus did?
Also it's not like Cirrus' catch fire all the time, first you need to crash it and then the odds are that they still won't catch fire (hopefully).
flyingcheesehead
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Interesting. I don't know where the Corvalis tanks are or if they're protected at all. It may also be a fleet size issue there - How many of them are out there? Did you also search on Columbia? How many crashes did you find, period? The problem with finding them all is that the Corvali have been through a lot of names. Lancair Columbia, Columbia Aircraft, Cessna, and when it's Cessna is it the Corvalis or is it just a Cessna 400?
True - But I'd rather not burn when I die. Of course on the Cirri, when they do burn they burn FAST...
Go to the NTSB database. Do searches on different makes. Use the search terms "thermal injuries" since for many years now this is what is used in reports when death is determined to be from fire. See what you find. Count the ones where the make is Cirrus. Look at Cessna and Piper and Beech. There is a often a huge difference between urban legend and the truth.
There was a Cessna 421 crash a few days ago. No flak on the Red Board about being a flaming death trap even though there was a horrendous fire. had it been a Cirrus the haters would have been all over it.
The Corvalis tanks are between two carbon fiber wing spars. It is a very nice feature from a safety standpoint.
In both cases it appears that the part was not safety wired when placed back on and in the first chute pull case it is believed the nut wasn't even tightened down fully. If there was no chute then there might be a crash with a fire and no one would ever know. One of the things about a chute pull is that the plane is basically intact.
Well, I know of an incident where a pilot had a prop strike, bent the blade out with a hammer and took off. Amazingly he wasn't flying a Cirrus.
I have a friend who (yes he admits he was crazy) took a DC3 off with only one engine working. He had an air freight company and didn't want to miss the delivery. That same guy was flying one day when there were only three planes in the air in the Atlanta area. Two of them were with his company. The icing was so severe all of the airlines were grounded.
As for the CO incident, how about the May 1969 flight of a Debonair into icing? This is also a CO icing fatality. I have the radio transcript for that flight and it is scary. I believe the NTSB record is DEN69A0048. Do you really think flying into ice is unique to Cirrus?
The main thing I see when I look at accidents is that no matter how fancy the plane, stupidity kills. I just don't see anything making this unique to Cirrus. Kennedy wasn't in a Cirrus.
I was thinking some more about this and it made me remember an incident that ended well; no damage or anything. A friend was VFR only but working on his instrument. He had a long trip to do and it involved instrument conditions so he took his instrument instructor along. During the flight they ran into ice. They called ATC but with ice on the antennas couldn't raise them They were getting close to their destination. Rather than turn around and return to clear air the instructor had my friend continue. The windscreen was iced over so they landed using synthetic vision. My friend was proud of the effectiveness of the synthetic vision. I think the instructor blew a great teaching moment and should have his certificate yanked but that's just me.I don't care if you can't reach ATC. Turn around, find clear air and talk to them when able and tell them what you did. Oh yeah, my friend flies a very nice Diamond DA40 with G1000 and Synthetic Vision.
bbchien
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Uh. That's kinda bs....
Are you saying he was lying? I don't know any reason he would. He's retired and we were talking about when he owned an air freight company. He said if you said you couldn't make the delivery you lost the business.
MachFly
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I haven't checked the Lancais because they are home build. Cessna Corvalis doesn't seem to be in the database. So the only thing I've checked was the Columbia 400. In total I found 25 reports.
MachFly
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Diamonds have exactly the same design (plus fuel cells).
How many wing spars does the Cirrus have?
Skylane81E
Final Approach
Sparky Imerson walked away from one, but when I met him several months later he was still suffering from the effects of the spinal fractures
Yes and I love the fuel tank design on Diamonds. Diamonds are better than almost all other planes in several things and this is one of them. I disagree that I would call the Diamond design a fuel cell but I could be wrong. I thought it was a metal tank inside a fiberglass wing, between dual spars with braided lines. Overall an excellent design. Probably the best out there.
Just one like many other planes.
I prefer the Diamond and Columbia arrangement when it come to tank integrity and have said so many times.
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MachFly
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The actual term that Diamond uses most of the time is "fuel chamber," however in the 42 manual (and only in the 42 manual) the term "fuel cell" is used a couple of times. I think all of this is because of the translation from german.
Yeah you got the general idea of how the fuel tank is attached in there. The thing is that the fuel tank is separated into two cells (in the 40), an inboard and an outboard cell. So that's why I'm calling them "cells," even though it's one fuel tank it's separated.
That's what I thought but wasn't 100% sure.
MachFly
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I usually call those "bladder tanks." Well whatever, we both know what were talking about.
It's the foam inside that keeps the fuel from dispersing in an accident that makes them a fuel cell.